Winamp should have populated those tags from the folder/filenames when you imported the wav files. Then, in the Winamp format converter, you specify the naming scheme with:
Winamp gives you these choices for parsing folder/filenames when importing files:
As you can see, Winamp assumes the second element in the filename is the Artist, and there doesn’t appear to be a way to change that. Since you have the album title in that position, Winamp will populate the Artist field with the album title.
As far as I can tell, your only option (using Winamp) is to
- import the wav files into Winamp using the “Smart” metadata reading option. Winamp will populate “Artist” with the album title.
- correct the “Artist” tag for each album before starting the conversion (using the naming scheme I posted above).
- Start the conversion. This will create the folder structure and filenames you specified.
The next option is to find a converter that gives you more control over the metadata reading pattern. I don’t know of one.